The Drophead nozzle aka "Knucklehead" is designed for navigating P-Traps, vertical drops and tight bends. The 3-Knuckle Leader guides the jetting hose around corners other nozzles won't reach. Use with our Ultra-Flex Stainless Braided Hoses or Bronze-Flex Hi-Flow mini-hoses to jet all types of P-traps and small drains.